A caravan of roughly 2,000 migrants bound for the United States early Saturday was halted by Mexican authorities only a few hours into their journey, according to officials.

The caravan, which consisted of migrants from Africa, the Caribbean, and Central America, left before dawn from Tapachula, a town in southern Mexico near the Guatemalan border, Reuters reported.

Many of the migrants who departed from Tapachula early in the morning had been held up there for weeks or months, awaiting residency or transit papers from Mexican authorities.

About 24 miles into their journey, federal police and national guardsmen blocked their path. Most of the group was detained and put on a bus back to Tapachula, while about 150 migrants returned by foot, witnesses said.